21747-085-01 | Bently Nevada 8.50m Armored Extension Cable

Introduction to the Bently Nevada 21747-085-01 Extension Cable

When machinery vibration threatens uptime, the 21747-085-01 from Bently Nevada provides a dependable link between probe and Proximitor. This extension cable is engineered for accurate signal transmission in demanding industrial environments.

With a cable length of 8.50 metres (335 inches), the 21747-085-01 supports system lengths of five or nine metres from probe tip to Proximitor. Its stainless steel armor option offers improved resistance to physical abuse, making it suitable for harsh applications.

Key Features and Technical Specifications

• Part Number: 21747-085-01
• Model: Extension Cable
• Manufacturer: Bently Nevada
• Cable Length: 8.50 metres (335 inches)
• Armor Option: 01 - With armor
• Power: -17.5 Vdc to -26 Vdc at 12 mA maximum consumption
• Calibrated Range: 80 mils (2.0 mm), begins at approximately 10 mils (0.25 mm) from probe face
• Scale Factor: 200 mV/mil (7.87 V/mm), ±4% if calibrated as a system
• Linearity: Within 0.8 mils (0.02 mm) of a 200 mV/mil straight line if calibrated as a system
• Frequency Response: 0 to 10 kHz (0 to 600,000 cpm); -5% at 10 kHz

These specifications ensure precise vibration measurement, critical for predictive maintenance programs.

Applications and Use Cases

The 21747-085-01 is ideal for rotating machinery monitoring, including turbines, compressors, and pumps. Its armored construction protects against physical damage in high-vibration areas. For example, in a petrochemical plant, the cable's corrosion resistance to chemicals like sulfuric acid and MEK ensures reliable operation.

Because the cable is part of a system with interchangeable probes and Proximitors, maintenance teams can quickly replace components without recalibrating the entire system. This reduces downtime and simplifies inventory management.

Installation and Setup

Proper installation is crucial for accurate readings. Ensure the cable is routed without sharp bends or excessive tension. The stainless steel armor provides added protection, but avoid crushing or kinking during installation.

Verify that the cable length matches the system requirement (five or nine metres total). Use only compatible Bently Nevada probes and Proximitors with the same part number to maintain interchangeability.

Maintenance and Reliability

Regular inspection of the cable and connectors helps prevent signal degradation. Check for signs of wear, especially at stress points. The operating temperature range for the probe and extension cable is -30°F to +350°F (-34°C to +177°C), so ensure the environment stays within these limits.

Relative humidity up to 95% (noncondensing) is supported, but avoid prolonged exposure to condensing moisture. Following the manufacturer's manual for periodic checks will extend the cable's service life.

Compatibility and Integration

The 21747-085-01 is designed to work with Bently Nevada 8 mm probes and compatible Proximitors. The system achieves a total length of five or nine metres, depending on the integral lead length. Probes and cables of the same length are completely interchangeable, simplifying field replacement.

For integration, ensure the Proximitor's power supply matches the -17.5 Vdc to -26 Vdc requirement at 12 mA maximum consumption. This ensures stable operation and accurate signal processing.

Common Questions About the 21747-085-01

Q: What is the cable length of the 21747-085-01?

A: The cable length is 8.50 metres (335 inches).

Q: Does the 21747-085-01 come with armor?

A: Yes, the armor option 01 indicates the cable is supplied with stainless steel armor.

Q: What is the operating temperature range for the extension cable?

A: The probe and extension cable operate from -30°F to +350°F (-34°C to +177°C).

Q: Can the 21747-085-01 be used with any Bently Nevada probe?

A: It is designed for use with compatible 8 mm probes and Proximitors with matching part numbers to ensure interchangeability.

Product Support and Availability

The Bently Nevada 21747-085-01 is available from Petro Auto Tech. Please verify current lifecycle status and availability with Petro Auto Tech before ordering. Our team can assist with technical questions and ordering information.